For maximizing manufacturing throughput on an industrial scale, metal sheets are oftentimes processed as a moving web of material. Thus, an elongate sheet of metal is driven past a series of manufacturing stations, where various machining or other operations are carried out on the moving web. One such operation involves applying a die set to the metal web, for deforming the web in a desired manner. For example, the die set may include a punch and a die, which, when pressed together with the web in between, form a hole in the web.
For carrying out punching operations on a moving web of metal, one or more punches are typically attached to the surface of a rotating drum or wheel, which is deployed on one side of the metal web. The other side of the metal web is supported in a complementary manner, e.g., a die or other support surface. The drum is carefully speed matched to the speed of the web. As the drum rotates, the punches on the surface of the drum are rotated into punching contact with the moving web, forming a hole or other desired feature. However, because the drum moves in a rotating manner whereas the web is moving linearly, there is a non-ideal interaction between the punch and web. In particular, not only does the punch move in a vertical direction with respect to the web, as in an ideal punching operation, but there is a concomitant degree of relative lateral motion as well. This “sweeping” or “wiping” motion of the punch causes the edges of the punch to laterally interact with the web, which can damage the punch or at least severely limit the times between required changeover or retooling.